By Neil Sperry :
January 26, 2014

Kalanchoes can be forced back into bloom by carefully controlling the light the plants receive.

Q. I was given a kalanchoe plant in full bloom as a Thanksgiving gift, and it has just finished flowering all these weeks later. Is it possible to grow it and bring it back into flower another time?

A. It will require some diligence. Kalanchoe is a succulent plant that is fairly closely related to jade plant and sedums.

Trim off seed heads, cutting the stems back into normal leafy growth. Repot it into fresh potting soil, and grow it in full morning sun with perhaps a little bit of afternoon shade in midsummer.

It won't stand freezing weather, so this process will have to begin on a windowsill now, then move out onto the patio in spring. Your biggest challenges will be in keeping the plant vigorous and compact until it's time to bring it back into flower.

Kalanchoes, like poinsettias, produce flower buds when nights get long.

The plant you received was manipulated in a greenhouse setting. That doesn't mean that you can't accomplish the same thing at home once your plant has regrown nicely. It just means that you'll have to keep it in total and uninterrupted darkness at night, full sun during the days to get it to set buds.

Q. As the garden season starts, I thought I might try rhubarb. I saw some in the store the other day. What do I need to know to grow it? We've just moved to Texas.

A. I hate to be the bearer of bad news, but rhubarb is not suited to Texas summers — it can't handle our heat.

Q. Should I trim dead branches off an oleander that has obviously suffered freeze damage?

A. If stems are turning drab green or brown, and if their outer surfaces are shriveled, those stems are dead and can be pruned away. However, if only the leaves have turned brown and the stems are still plump, you should wait to see if they sprout foliage in a few weeks.

Q. I have a bed of liriope that I would like to use for new plants to start another bed in my yard. When and how should I do that?

A. Start by trimming away any dead foliage left over from cold spells. That will give you a clearer vision of where the plants are.

Use a sharpshooter spade to remove small clumps within the bed. Do it in a way that the remaining liriope will conceal the empty spots.

Your new plants' root systems should be abou the size of a tennis ball. Space them on 10-inch centers in the new bed. Late January through early February is the best time to do this dividing and transplanting, before new spring growth begins.

Liriope starts growing very early, so don't wait too long.

Q. I planted ryegrass last October to cover a portion of our yard where we had taken down a building. So it wouldn't look odd, I just seeded the entire backyard. But the grass looks tired right now, as if it hasn't endured the winter very well. How soon can I apply a fertilizer to it?

A. You can fertilize it before any warm spell that will last several days. Because part of it is overseeding other turf, I would suggest using a half-rate application.

Normally it's best to apply a fertilizer and then water it in, but if water curtailments in your area don't allow that, you may want to wait the whole thing out. The grass will rebound by February. Or, if you're able to feed just ahead of a soaking rain, that might be an option, although that's usually not the best plan, since both organic and inorganic fertilizers are subject to nutrients being leached into runoff when rains turn out to be heavier than expected.

Q. I've been doing some pruning on an old elm tree to remove a couple of dead branches, and I have noticed a cavity in the trunk about 15 feet off the ground. Should I try to get up there and fill it? What happens if I don't?

A. Cavities usually show up where a branch or even a twig has died or broken and when the stub has been left in place. That stub blocks the growth of protective bark across the wound, and by the time the stub finally falls away, there is active decay down into the trunk.

Often, other branches directly above or below the cavity become swallowed up in the decay. Check to see if that's the case with your tree.

Sometimes you can end up with just a cylinder of bark and outer tissue supporting a massive elm — just waiting for the right windstorm.

I recommend having a certified arborist, or at least a Texas Master Certified Nursery Professional, look at the tree. Do not attempt to fill the cavity. It can block normal healing.